1. Field of the Invention
An aspect of the present invention relates to a charger and discharger for a secondary battery, and more particularly, to a bidirectional DC/DC converter type charger and discharger for a secondary battery, in which the range of voltage is extended so that charging and discharging of the secondary battery can be performed by a single device.
2. Description of the Related Art
In general, a bidirectional power converter circuit converts a high voltage into a low voltage in a buck mode, and converts a low voltage into a high voltage by using a back electromotive force in a boost mode. In this instance, it is effective to control the conversion in a pulse width modulation (hereinafter, referred to as a ‘PWM’) method by using one or more metal oxide semiconductor field-effect transistors (MOSFETs). The amplitude of a voltage outputted from the bidirectional power converter circuit is determined with a PWM duty ratio.